Different research efforts have focused on improving the Muscle Quality Index (MQI) to enhance muscle function in the adult population. However, in the adolescent population, these assessments not only seem to be scarce but also the methods used to assess MQI appear to be even more limited. Therefore, the objectives were: i) To determine the most commonly used tests for determining MQI in healthy children and adolescents or those with some pathology, and ii) to observe the number of studies that have evaluated MQI in said population. This study corresponds to a systematic review that was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The search limits were articles published from the start date until the year 2023 that included assessments allowing for an explicit MQI outcome in children or adolescents. The search identified articles published in the Web of Science, Scopus, SPORTDiscus, PubMed, and Medline databases. A total of 16 articles were included in the systematic review, which were stratified according to the different methods used to assess MQI. There is a wide variety of tests to determine MQI in children and adolescents, which sometimes leads to a lack of heterogeneity and reproducibility of results in assessment protocols. Despite this, the incorporation of new tests that include variables of muscle strength, muscle power, and muscle volume from the same body area is sug-gested.